Heat is supplied to a test tube containing 100g of ice at its melting point. The ice melts completely in 1 min.What is the power rating of the source of heat? [Latent heat of fusion of ice = 336Jg-1]
See more
1994
When 100g of liquids L1 at 78oC was mixed with Xg of liquid L2 at 50oC, the final temperature was 60oC. Given that the specific heat capacity of L2is half that of L1, find x
See more
1994
To produce a parallel beam of light from a concave mirror, the distance at a which the lamp should be placed from the mirror is equal to
See more
1994
The note produced by a stretched string has a fundamental frequency of 400Hz. If the length of the string is doubled while the tension in the string is increased by a factor of 4, the frequency is
See more
1994
A pipe of length 45cm is closed at the end. Calculate the fundamental frequency of the sound wave generated in the pipe if the velocity of sound in air is 360ms-1 [Neglect end correction]
See more
1994
The fundamental frequency of vibration of a sonometer wire may be halved by
See more
1994
The sound from a source travelled to the bottom of the sea and the echo was heard 4s later. If the speed of sound in sea water is 1500ms-1 the depth of the sea is
See more
1994
If the Nigeria flag (green, white, green) is viewed in pure yellow light, which of the following set of colours would be observed on the flag?
See more
1994
In a projection lantern of focal length f, the object distance u, is such that
See more
1994
An object is placed directly below a glass block of thickness 3.0cm. Calculate the lateral displacement of the object if the refractive index of the glass is 1.5.
See more
1994
An object is placed in front of a converging lens of a focal length 20cm. The image is virtual and has a magnification of 2. What is the distance of the object from the lens?
See more
1994
Light of frequency 6.0 x 1014 Hz travelling in air is transmitted through glass or refractive index 1.5. Calculate the frequency of the light in the glass
See more
1994
Which of the following are found in the receiver but not in the microphone of a telephone handset? i. Diaphragm. ii. soft iron pole pieces. iii. permanent magnet. iv.carbon blocks
See more
1994
Two capacitors R1 = 4\(\Omega\) and R2 = 5\(\Omega\) are connected in parallel across a potential difference. If P1 and P2 represent power dissipated in R 1 and R2 respectively, then the ratio P1 : P2 is
See more
1994
A capacitor 8\(\mu\)F is charged to a potential difference of 100V. The energy stored by the capacitor is
See more
1994
When a biro pen rubbed on a dry silk cloth is moved very close to a piece of paper on a dry table, the pen is found to pick up the paper. This is because
See more
1994
Which of the following has the lowest internal resistance when new?
See more
1994
If light with photon energy 2eV is incident suitably on the surface of a metal with work function 3eV, then
See more
1994
A certain radioisotope of \(^{235}_{92}U\) emits four alpha particles and three beta particles. The mass number and the atomic number of the resulting elements respectively are
See more
1994
If two parallel conductors carry currents flowing in the same direction, the conducts will